The present invention relates to the field of elevator control, and in particular to control of a group elevator system to facilitate transporting of a large item.
Conventional group elevator systems include hall call modules near the elevators on each floor. Typically, the hall call modules include up and down buttons that are pressed by passengers when elevator service is desired. Each hall call module is assigned a network address that an elevator controller uses to associate the hall call module with its floor location. When one of the buttons on the hall call module is pressed, the elevator controller assigns an elevator that will most efficiently deliver the passengers in the desired direction. The elevator controller determines which floor to send an elevator to based on the network address of the hall call module on which a button was pressed.
Recently, elevator systems with destination entry have been introduced. In a destination entry system, passengers register their destination floors on a destination entry input device before a car is assigned. The group elevator system assigns each passenger to an elevator that most efficiently transports him or her to the desired destination floor. Passengers register their destination floors on destination entry devices, which may take the form of a numeric keypad or a touch screen display.
Large items to be transported between floors in an elevator can consume much of the volume or use a substantial portion of the maximum rated load for the elevator car. This may disrupt efficient transport of passengers and other loads in a group elevator system, since the elevator controller may be unable to determine that a passenger making a dispatch request is accompanied by a large item. For example, in a destination entry type system, when a passenger with a large item enters his or her destination floor, the controller may assign the passenger to an elevator that already includes a large number of people. Similarly, when a passenger with the large load is assigned to an empty or nearly empty elevator, the controller may subsequently assign additional passengers to the elevator. These circumstances may result in overcrowding or overloading of the elevator car, or passengers may be required to re-enter their destination and wait for a different elevator.